Watch Strangers on the Street Discuss the Benefits of Keeping Backup Boyfriends and Girlfriends

Raise your hand if you've ever been in a relationship but kept texting or G-chatting with someone else in a flirty way...you know, just as a contingency plan. This phenomenon of having a "backburner" is actually pretty common, says intimacy expert Laura Doyle, author of First, Kill All The Marriage Counselors. But don't take her word for it—watch men and women talk about their side pieces: